Heathrow has reopened one of its two runways but said more than 650 flights were cancelled because of today’s heavy snow falls.

Southampton airport has also reopened and passenger were asked to check in as normal even though the airport warned of delays for the rest of the day.

However, London City airport, where about 15cm of snow fell, said it expected to remain closed for the rest of the day.

Airports’ response to the snow – said to be the heaviest fall for 18 years – began to attract criticism, as the Met Office warned that another 10 to 18cm could fall overnight, bringing more disruption.

Allen Miller, joint owner of single-parent specialist tour operator Small Families, commented on ttglive.com that airports had had three days' warning to prepare for the snow, and he called for heads to roll.

“I have never known an airport north of the Arctic Circle in Finland to close through snow and I personally have landed very safely in Finland, Sweden and Canada in heavy blizzards,” he said.

BAA said it had deployed its full snow operation of 58 snow cutters, ploughs and de-icers since 3pm yesterday and staff had been working double shifts.

“The snowfall has been the heaviest in decades and has meant that our operation is even finding it difficult to find empty space to put the snow,” it said in a statement.

British Airways has cancelled all Heathrow flights until 5pm and BMI has also cancelled most of its schedule.

• Send us your snow photos (2 Feb 2009)